1823.] Mr. DanielVs Meteorological Essays, 453 



observes and classifies the forms of clouds, remarks their motion, 

 their production and disappearance ; and from these indication^ 

 he is often enabled to foretel changes of weather, which to the 

 careless observer seem the wayward results of chance and acci- 

 dent. Besides these more constant phenomena, it is his busi- 

 ness to examine and record the occasional ones of thunder and 

 lightning, the aurora boreahs, and other luminous meteors, 

 which, though seemingly casual, are no doubt parts of a regular 

 chain of events, which we may hope to see one day spread 

 before us in unbroken continuity. In the study of atmospherical 

 phenomena there is, therefore, a wide scope for the ingenious 

 inventor of refined and delicate instruments ; for the careful and 

 patient observer of facts ; and for him also who is capable of tak- 

 ing a wider range, and of connecting individual truths into an 

 harmonious and durable system. 



In our own language there are but few works that have been 

 exclusively devoted to the subject of atmospherical phenomena. 

 In 1787, Mr. Kirwan published a small octavo volume entitled, 

 " An Estimate of the Temperature of different Latitudes," which, 

 among some errors, contains much valuable matter, collected 

 with great pains from a variety of sources. In 1793 appeared a 

 small volume by Mr. Dalton, entitled, " Meteorological Obser- 

 vations and Essays," which does no discredit to the subsequent 

 fame of that distinguished philosopher. This was followed, after' 

 an interval of several years, by Mr. Forster's " Researches," 

 and Mr. Luke Howard's valuable work, ^^ On the Climate of 

 London." To these, indeed, may be added several detached 

 treatises in the different Encyclopsediee, under the heads of 

 Barometer, Climate, Cold, Hygrometry, Meteorology, Rain, 8cc. 

 and in the Transactions of the Royal and other Societies, and 

 the various periodical journals, a great mass of useful informa- 

 tion is spread over a wide surface. It would be a most accept- 

 able service, therefore, to the meteorological inquirer, if all this 

 scattered knowledge were reviewed and methodized. He would 

 then be placed on an eminence, from which, surveying what is 

 known, he would be able to mark the bearings of unexplored 

 regions. This kind of history is not the object of Mr. DanielFs 

 work, which is rather to be considered as a train of original 

 investigations ; and antecedent discoveries are related, chiefly as 

 they bear upon the subjects of his inquiries. In these inquiries 

 he has shown considerable ingenuity and great industry ; and 

 if we should doubt of the soundness of some of his conclusions, 

 or the value of a part of his labours, it is still with feeUngs of 

 respect for the general merits of his performance, and with 

 approbation of the fairness and candour with which he has 

 treated those who have written before him on the same topics. 



The work consists of five separate essays : 1, " On the Con- 

 stitution of the Atmosphere." 2. " On the Construction and 

 Uses of a new Hygrometer," 3. "On the Radiation of Heat iu 



